Rolling of channel sections with wide flanges



March V15. 1932.. J. MEISER 5 ,0

ROLLING OF CHANNEL SECTIONS WITH WIDE FLANGES Filed Jan. 13. 1930 2Sheets-Sheet 2 l'bventar B vfiwzeb z M Patented Mar. 15, 1932 .J'OS EFMEISER, OF DOBTHURD, GERMANY BOLIJINGDF CHANNEL SECTIONS WITH WIDEFLANGES Application flled'ifanuary is, 1930, Serial No.

relates to method of rolling especially those with wide to provide adesirable im- My invention channel sections, flanges and aims provement.I

In rolling metal sections. by the operation of conducting metal barsthrough passes comprising pairs of rolls that gradually approximate theform and shape of the finished section. it is necessary for thecentre ofgravity of the cross sectional surface of each section (corresponding tothe pass for the time being) to lie nearly as possible in a line drawnmidway between the axesof the two rolls and parallel therewith. 1

When dealing with" wide-flange channel sections wherein the centre ofgravity is situated very near the web of the iron, the fulfillment ofthe above condition of the rolling art (as is essential for steadyrunning) has heretofore made it necessary to very considerably weakenthe roll that acts on the hollow side of the channel, at the partoccupied by the flanges. Consequently, either a rapid destruction of therolls had to be counted upon, or stronger and heavier rolls had to beused.

My invention obviates this disadvantage or necessity for stronger andheavier rolls which are costly, in that, while maintaining the totalwidth of the section always the same, I cause the web of the roughedsection, between the flanges, to draw towards the interior of thechannel, thus displacing the centre of gravity of the cross section awayfrom'the web and in the direction of the flanges. the web beingflattened out only in the final finishing pass. At that stage, however,the weakening of the rolls is not so important, the final pass beingsituated near thebearings of the rolls.

0 A practicable embodiment of the invention is diagrammaticallyillustrated in the accompanying drawings, in which1:--

Fig. 1 shows a firstpair of roughing rolls in side elevation; r

Fig. 2 is a similar elevation Iota second pair of roughing rolls 4 gig.3 shows the pair of finishing rolls;

Fig. 4 shows how the "displacement of the rolling-mill practice.

centre of gravity is efi'ectedfby modifying 420,577, aim in GermanyFebruary 25, 1929.

the shape of the roughed sections according to my invention.

It is assumed in the representation that 2. rolled bar must be putthrough ten passes denoted at 1, 2, 3 et seq. to 10. In the first pass,1, it is given the cross sectional form A, and thereafter in successionthe forms B, C, D by the first pair of rolls R and R then it is given insuccession the forms E, F, G by the second pair of rolls R and R andlastly it is given in succession the forms H, J, K between the finalpair of rolls R and B In each of Figs. 1 to 3, the central axes of saidpairs of rolls (R and'R R and R and R and R are indicated by thedot-and-dash lines aa: aa, while the line of action, midway between saidaxes and crossed at equal speed by corresponding points of the co-actingpair of rolls, is indicated by 6-6. As already stated, it is necessaryin rollingmill practice to have the centre of gravity of the crosssectional surface of each of the several'forms A, B, C et seq. to Kcoincide apwithout having to weaken the rolls unduly in places, I givethe roughed sections forms that progressively approach the shape of theletter M, so that the web of the channel sectionwill be depressed orrecessed in the centre like a saddle, this shape being retainedup to thelast roughed section J, shown 4 at the pass 9 in Fig. 3.

Fig. 4=- shows what transverse displacement and what saving in thediameter of the rolls I efiect in this manner. The'heavy outline,

obliquely hatched, illustrates the course of the web of a roughedsection approximately corresponding tothe form-J in the pass 9,

whilst the adjacent thinner outline shows the penultimate shape obtainedin existing thisshape is substantially straight at c; The axis ofgravity of this usual shape is indicated by the line H. Now, as theresult of my givmg the web the curved form repre- It will be seen thatroll.

formative blank in the successive stages ofv I '50 I sented by d e fand, at the same time, drawing the flanges of, the section slightly intowards the centre, as shown, the axis of gravity is displaced from theposition H to y--y and the centre of gravity is displaced, by

the distance .2, from the point S to the point S in the direction of thefree ends of the flanges. It will be apparent that to maintain theaforesaid condition while employing thev usual shapes of roughedsections with straight web a, the roll R would have to be cut deeper, bysaid distance 2, in the centre in pass 9, and would therefore beconsiderably more liable to damage in rolling.

By not pressing the web out flat until the final pass 10, it isunnecessary to recess the roll R more deeply except in this particularportion which is near the bearing of the Consequently, the roll issubjected to less stressing as a whole, and has a lesser tendency tofracture.

Having now particulary' described and ascertained the nature of my saidinvention and in what manner the same is to be performed, I declare thatwhat I claim is 1. In amethod of producing channel sections of metalwith wide flanges by passing a blank or bar of the metal through asuccession of forming spaces or passes between oppositely rotatedpressure rolls, the improvement which consists in drawing theintermediate or web portion of theforming section inward toward thecenter of the channel in the successive stages while maintaining thewidth thereof always the same, so that the centre of gravity of thesection will be displaced in the direction of the free ends of itsflange portions, and in the final step or pass back-drawing andflattening said web portion while still maintaining the section at thesame width.

2. In the process of producing channel sections of metal with widemarginal flanges by passing a blank or bar of the metal through aplurality of successive forming spaces or passes between oppositelyrotated press rolls, the improvement which consists 1n drawing thecentral portion of the formation inwardly toward the center in the meandirection of its sides simultaneously shaping into the flange portionsof the finished section without varying the width of the piece-from thatoriginally, so as to displace the centre of gravity of the formingsection in said direction or toward. the free ends of its flangeportions'during the suc cessive press actlons, and finally back-drawingand flattening out said central portion forming the web of the sectionwhile maintaining it still at the original width.

3. The improved' ,.method of producing channel sections of metal withwide marginal flanges, characterized passing a blank or bar of the metalthrough a progressive succession of forming spaces or passes be,

tween oppositely rotated rolls pressing the same into shape; drawing thecentral or webforming portion of the graduallyshaped section inwardlytoward the center in the mean direction of its simultaneously formingflange portions without varying the width of the section from that ofthe original blank, so as in the successive stages to displace thesections center of gravity in said direction toward its free ends; andin the final step or pass drawing said central web-forming portion inoposite direction to a flat plane with flange portions at desired anglethereto in the completely formed section, while maintaining the latterstill at the same width.

4. A method of rolling'channel sections oi metal having webs and wideflanges which consists in passing the blank through roughing passes andthen through a finishing pass between shaping rolls, maintaining in allsaid roughing passes the metal "to "a constant width and simultaneouslyin said roughing

